"jQuery is a fast and concise JavaScript Library that simplifies HTML document traversing, event handling, animating, and Ajax interactions for rapid web development."

Prototype JS

"Prototype is a JavaScript Framework that aims to ease development of dynamic web applications."

Google Code - AJAX Libraries API

"The AJAX Libraries API is a content distribution network and loading architecture for the most popular, open source JavaScript libraries."

Pixel Mixer

"High quality icons for web applications, software and GUI design."